In this article, Christopher Grobe explores the history of the telegraph machine on the nineteenth- and early twentieth-century stage. Structured around a deep analysis of William Gillette's Secret Service, this article also surveys American, British and French telegraph plays and considers such extra-theatrical “performances” as technical demonstrations and early baseball broadcasts. Grobe ultimately argues that telegraphy transformed the dramaturgical habits and acting styles of nineteenth-century theater, turning them realist and proleptically modern. At the same time, these plays reveal new, emerging understandings of the human, the global, and the live.